ToonBoom crashes: QTCore4.dll

Try to drag large set of elements onto parent peg, OR, drag large project contained in parent peg to library and ToonBoom crashes each time.

Windows Application Log lists QtCore4.dll failure. (I’m assuming this is part of the Trolltech QT4 related files used to create ToonBoom).

Anybody else experienced this?
ToonBoom seems fairly reliable appart from this…

I have noticed that the project is much larger than I expected - mainly from imported/vectorized bitmaps that were larger than thought. Also the vectorization seems to increase the size of the PNG image by a factor of between 6 and 10. Using jpegs doesn’t help - they have no alpha layer and they get increased by 46x (!) when imported and vectorized.

I can work to reduce the project size but it was never intended for the web and it is only 30 seconds long.

So…I’m curious to know whether there is an upper limit (either in ToonBoom and/or QT4) on what can be dragged and dropped…Is this something I need to keep track off? Do I need to keep the number of frames in a scene/project below a certain limit?